Textile pirn



Feb. 13, 1968 w. 1.. SCHMIDT TEXTILE PIRN ZSheets-Sheex 1 Filed Jan. 21, 1966 alddrllflllllll INVENTOR. Iii/11am Liz-$10141; BY

BY 62m 631 3,368,767 TEXTILE PIRN William L. Schmidt, Gastonia, N.C., assignor to Cocker Machine & Foundry Company, Gastonia, N.C., a corporation of North Carolina Filed Jan. 21, 1966, Ser. No. 522,212 9 Claims. (Cl. 24246.21)

ABSTRACT OF THE DISCLOSURE A driving connection between a pirn and a whorl designed to provide accurate static centering of the pirn on the whorl and to then lock the pirn concentric with the whorl b an automatic cam action as rotation begins.

This invention relates to a pirn, or sometimes described as a bobbin, that is particularly adapted for use as a yarn carrier in the textile industry. It is customary practice in the textile industry to package yarn intermediate to various processing operations by winding the yarn on a tubulair pirn, that may then be readily detached from the winding spindle and used to transport the yarn package to a subsequent operation, where the yarn is stripped from the pirn for further processing.

Because of the trend to higher acceleration rates and winding speeds, pirns must now be of precision construction and balance to minimize vibration, and of rugged design adequate to continued reuse. To this requirement, pirns now are generally made from a length of precise round tubing of adequate material strength, one end of which must be of a configuration suitable for a positive driving engagement with the winding spindle, and further provided near each end with devices suitable to centering the pirn with the spindle axis of rotation. It has been found economically advantageous to mold the driving engagement as a separate plastic component, which is then securely aflixed to the tube end. The pirn is driven from its lower end, and may have its upper end plugged, or otherwise arranged to receive an identifying device for the yarn packaged on it. The exterior surface of the pirn onto which the yarn is wound may be protected with an inexpensive disposable sleeve to absorb damage.

This invention is concerned with pirns arranged for support and positive driving engagement at the lower end on a vertical winding spindle and whorl assembly of Various designs.

A recurring problem of the art has been to provide a pirn of precise high-speed design that may repeatedly and efiiciently be affixed on and maintained in concentric winding position and driving engagement with the spindle, without excessive dynamic vibration and/or damage to the driven end of the pirn. The spindle design in most universal current use provides a polygonal projection on the whorl, over which a similar polygonal socket of slightly larger dimension on the driven end of the pirn is seated in approximate static concentricity. As spindle rotation begins, a slight relative rotation occurs until the clearance is overcome by engagement between the angular corners on the whorl and the fiat surfaces of the socket. On repeated use, the whorl corners tend to indent the socket surfaces in random manner, which tends to permit a progressively increasing eccentricity of the pirn end and create an objectionable and dangerous vibration.

Another common spindle design provides a pair of lugs, transverse to the spindle axis and circumferentially displaced 180 degrees apart, for driving engagement with corresponding slots in the pirn end, requiring that the pirn be rotated substantially to seat. This design relies on the slightly loose fit of a circular collar in the pirn end over either the spindle itself, or over a round projection of the United States Patent T 3,358,767 Patented Feb. 13, 1968 concentric with the spindle axis by an automatic camaction as rotation begins, both without sacrifice of doffing efficiency.

Referring now to the drawings:

FIG. 1 represents a side sectional view of one specific embodiment of pirn constructed in accordance with fea- I tures of this invention, the pirn being shown in position on a driving whorl and spindle which are shown in full elevation;

FIG. 2 is an enlarged view of the driving portion of the whorl and pirn appearing in FIG. 1, with the pirn shown in section;

FIG. 3 is a sectional view taken as indicated by the lines and arrows IIIIII which appear in FIG. 2; and

FIGS. 4, 5, 6 and 7 are sectional views similar to FIG. 3, showing modified forms of driven ends in accordance with this invention.

The portion of the specification which follows is directed to a specific description of the particular forms of the invention selected for illustration in the drawings. It will be appreciated that specific terms will be utilized for the sake of clarity and that these are not intended to limit the spirit or scope of the invention which is defined in the appended claims.

Turning now to the apparatus appearing in FIGS. 1-3, the pirn there shown has an elongated cylindrical barrel 10 having a plug 11 at its upper end, and a slidably removable sheath 12 covering a substantial part but not all of the barrel 10 and curled over the upper portion of the plug 11. Located at the base of the pirn is a driven portion 13 which will be described in more particular detail hereinafter. The pirn, as shown, is disposed on a whorl having a polygonal driving portion 14 composed of fiat faces 14a, a conical shoulder 15 and a rounded upper portion 16. Extending through the whorl is a spindle 17 of the usual type. Located at a point spaced along the axis of the pirn toward its upper end is a centering collar 20 which engages the spindle 17 near its tip 21.

Referring to FIG. 2, it will be observed that the insert 13 at the driven end of the pirn has a generally cylindrical periphery 22 which fits closely inside the sheath 12, has an inwardly shouldered portion just beneath the lower end of the barrel 10 and an upwardly extending flange 23 which is spaced outwardly from the rounded upper portion 16 of the whorl but which fits snugly within the end of the barrel 10. The fit between the flange 23 and the barrel 10 is so tight as to transmit driving rotation from the flange 23 to the barrel 10.

The plug 13 is also provided with an inwardly extending ring 24 which is circular in cross-section and fits loosely against the vertical cylindrical surface of the whorl portion 16, and which has a downwardl and outwardly angled conical surface 25 which rests upon the conical surface of the shoulder 15 of the whorl, and extends outwardly beyond the outer extremity of the portion 15, as appears at both the left and right hand portions of FIG. 2. The insert then terminates in a downwardly extending flange, the lower end of which is spaced above the upwardly facing surface of a shoulder 26 which is on the whorl at a location below the driving portion 14 of the whorl.

Turning now to FIG. 3, it will be appreciated that the inner surface 30 of the driven portion of the insert 13 is substantially multi-lobal in shape and that it is loosely contacted by the corners 14b of the polygonal driving portion 14 of the whorl. As shown in FIG. 3, due to the multi-lobal shape 30, six opposed corners (and, after relative rotation, only three) of the driving portion of the w-horl contact the inner periphery of the driven portion of the pirn. The letters I), D, D have been applied to altcrnate corners, together with associated arrows, to indicate that the starting rotation of the whorl in the direction of the arrow a produces components of force in the general direction of the arrow d, thus carnming the pirn with respect to the whorl and assuring an accurate centering of the pirn and its maintenance in centered relationship as long as rotation is sustained. This is an important and advantageous feature of this invention and is directly related to the fact that the driven portion of the pirn has a curvilinear inner configuration which includes purely arcuate surfaces which curve from a greater distance from the center of rotation to a lesser distance from the center of rotation.

Turning now to FIG. 4 of the drawings, a modified form of the invention is shown. The curvature of the driven portion of the pirn has alternately a concave portion 40 and a convex portion 41, thus forming a multiplicity of inwardly thickened portions or lobes 42 in the driven portion of the pirn. The dot-dash lines in FIG. 4 show the position taken by the whorl after slight relative rotation, and show how the whorl drives outwardly angularly into the lobes 42, applying forces as indicated by the arrows b, such being camming forces which earn the pirn in such a manner that it is positively centered and locked during the rotational acceleration and running periods.

FIG. 5 shows a modified form of whorl and a pirn structure to accompany such modified form of whorl. The whorl has three convexly curved surfaces. 43- and three fiat surfaces 44. Again, the driven portion of the pirn is provided with alternating concave surfaces 40 and convex surfaces 41 forming lobes 42. The function of the lobes in conjunction with the whorl remains the same, and the camming action is indicated by the arrows in FIG. 5.

FIG. 6 shows a structure similar to FIG. 4, except that only two lobes are provided. These lobes, again, have alternating concave portions 40' and convex portions 41 forming only two lobes 42, the balance of the inner periphery of the driven portion of the pirn in FIG. 6 being shaped in accordance with a section of a cylinder. In FIG. 6, the whorl drives outwardly against the pirn in opposed locations, as indicated by the arrows appearing in FIG. 6.

FIG. 7 shows a structure similar to the preceding three figures, except that the inner surface 30 of the driven portion of the insert 13- is substantially oval in shape. Because of the oval shape 30, only four opposed corners (and, after relative rotation, only two) of the driving portion of the whorl contact the inner periphery of the driven portion of the pirn. The letters D, D indicate the points of contact resulting from starting rotation of the whorl.

Accordingly, it will be appreciated that the pirn according to this invention is adapted to be driven by a rotating whorl having a driving section which includes driving projections and/or surfaces rotating in a circular path. The driven end of the pirn has a central aperture, in all cases, of curvilinear configuration arranged about the center of rotation of the path, for driven contact with the driving projections and/or surfaces of the whorl. Preferably, as stated, the whorl has a conical shoulder located above the driving section and the driven end of the pirn is obstructed by a supporting means extending into the central aperture for supporting and centering the pirn on the shoulder. The lower end of the pirn is preferably spaced above the bottom platform 26 of the whorl, thus providing freedom of tilting motion for the pirn in conjunction with the camming motion of the curvilinear driven portion of the pirn, thus assuring prompt and accurate establishment of a cam-centered and locked driving relation. These are important and advantageous features according to this invention.

Although this invention has been described with reference to specific embodiments thereof, it will be appreciated that many variations may be made without departing from the scope of the invention. For example, equivalent elements may be substituted for those disclosed and claimed, parts may be reversed, and certain features may be used independently of other features, all without departing from the spirit and scope of this invention as defined in the appended claims.

The following is claimed:

1. A pirn adapted to be driven by a rotating whorl having a driving section including driving portions rotating in a circular path, said pirn comprising an elongated hollow tube of substantially circular cross-section with a lower driven end having a substantially central aperture of at least partly curvilinear inner configuration arranged about the center of rotation of said whorl, said whorl having a different configuration than said configuration of said pirn and being provided with circumferentially spaced portions for engaging said at least partly curvilinear configuration of said pirn only at circumferentially spaced points and portions intermediate said first mentioned portions out of engagement with said pirn con figuration, said configuration being characterized in that engagement between said configurations always takes place on a curved part of said pirn configuration to provide a cam action as rotation of said pirn begins to thereby lock the pirn concentric with the axis of rotation of said whorl.

2. The pirn defined in claim 1 wherein said whorl has a substantially conical shoulder above said driving section, and said driven end of said pirn is partially obstructed by a conical supporting means extending into the central aperture for centering and supporting said pirn on said shoulder.

3. The pirn defined in claim 2 wherein the supporting means extends substantially closer to said center of rotation than does the inside of the pirn barrel.

4. The pirn defined in claim 1 wherein the curvilinear inner configuration includes at least two arcuate surfaces each of which curves from a greater distance from said center of rotation to a less distance from said center.

5. The pirn defined in claim 1 wherein said curvilinear configuration is a series of smoothly connected alternate convex and concave curves.

6. The pirn defined in claim 1 wherein said curvilinear configuration is polylobal.

7. The pirn defined in claim 1 wherein said curvilinear configuration is oval.

8. The pirn defined in claim 2 wherein the pirn is supported completely on said conical whorl shoulder, independent and clear of any other contingent surfaces.

9. The pirn defined in claim 2 wherein a centering collar is provided within said pirn and a spindle is provided concentric with said whorl and extending through the lower part of said pirn and through said collar and having its tip extending above said collar.

References Cited UNITED STATES PATENTS 2,463,591 3/1949 Bauer 242-46.2l 2,625,335 1/1953 Atwood 242-4621 3,132,817 5/1964 Atwood et al. 242-4621 FOREIGN PATENTS 892,152 3/1962 Great Britain.

STANLEY N. GILREATH, Primary Examiner. 

